CAIRO — Egypt’s leading opposition group urged its followers yesterday to vote against an
Islamist-inspired draft constitution, ending weeks of indecision over whether anti-government
forces should boycott the referendum, which begins this weekend and pits secularists against the
Muslim Brotherhood.

The move by the National Salvation Front is a crucial test of its popularity against President
Mohammed Morsi and his Islamist supporters. The opposition movement has revived the country’s
revolutionary fervor but has been marred by divisions and poor organization, which are expected to
be exploited by the Brotherhood’s vast grassroots network.

The National Salvation Front “decided to call upon the people to go to the polling stations and
reject the draft by saying ‘No,’ ” said Hamdeen Sabahi, a former presidential candidate and one of
the group’s leaders. “The people will rally at the polls and have a chance to topple the
constitution.”

Perhaps sensing a possible setback, he added: “The referendum is not the end of our
journey."

The Front said its decision was contingent upon judicial oversight, international monitors and
increased security at polling stations.It is unclear whether those demands can be met. Many judges,
angry at a recent power grab by Morsi that weakened the courts, have refused to supervise the
referendum. That forced the Islamist leader to announce that voting would be held over two
successive Saturdays — beginning this weekend — so participating judges can be rotated across the
country.

A political compromise appears increasingly elusive as the president pushes ahead for the
referendum and the opposition attempts to rally voters against a document it fears will strengthen
Islamist designs and jeopardize civil rights and freedom of expression.